Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
1.
Environ Sci Pollut Res Int ; 31(18): 26355-26377, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38530521

RESUMO

Urban rivers are affected at different levels by the intensification of human activities, representing a serious threat to the maintenance of terrestrial life and sustainable urban development. Consequently, great efforts have been dedicated to the ecological restoration of urban rivers around the world, as a solution to recovering the environmental functionality of these environments. In this sense, the present work aimed to investigate the effectiveness of interventions carried out aimed at the recovery of urban rivers, through a systematic review of the literature between 2010 and 2022, using the search term "rivers recovery." The results showed that there have been notable advances in the implementation of river recovery programs in urban areas around the world between the years analyzed. The ecosystems studied were affected, for the most part, by the increase in the supply of nutrients from domestic and industrial effluents, in addition to having highly urbanized surroundings and with several changes in land use patterns. The preparation of this literature review made it possible to demonstrate that the effectiveness of river recovery is extremely complex, since river recovery projects are developed for different reasons, as well as being carried out in different ways according to the intended objective.


Assuntos
Rios , Rios/química , Ecossistema , Recuperação e Remediação Ambiental/métodos , Humanos , Conservação dos Recursos Naturais
2.
Holist Nurs Pract ; 37(6): 311-317, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37851347

RESUMO

Reiki is a philosophy and healing technique that directs the use of vital energy (ki) for energy rebalance, as well as healing, in a holistic sense, of physical, emotional, mental, and spiritual processes. The practice is part of the integrative and complementary practices recognized by the World Health Organization. This study aimed to evaluate the Reiki effects on people's life quality perception, by using the World Health Organization Quality of Life-BREF (WHOQOL-BREF). We analyzed the answers of 144 individuals, and the data were categorized in quartiles according to the number of Reiki sessions attended. The results of each question and dimension of the questionnaire were analyzed by Student's t test (individual questions) and analysis of variance (dimensions). We observed significant improvement in the perception of physical pain, need for medical treatment, meaning of life, physical environment, availability of money, availability of information, locomotion, work capacity, access to health, place of residence, and transportation facilities. Reiki sessions have improved people's quality of life perception in many aspects, proving its therapeutic efficacy in a broader approach to health promotion.


Assuntos
Qualidade de Vida , Toque Terapêutico , Humanos , Qualidade de Vida/psicologia , Inquéritos e Questionários , Organização Mundial da Saúde , Percepção
3.
Hist Cienc Saude Manguinhos ; 29(3): 853-861, 2022.
Artigo em Português | MEDLINE | ID: mdl-36074366

RESUMO

The material memory of the 12th International Congress of Zoology, held in Lisbon in 1935 includes insignias - the starfish - and caricatures of zoologists. Through an investigation of the archives at the University of Lisbon's National Museum of Natural History and Science, we intend to investigate the material landscape as conceived by the zoologist Artur Ricardo Jorge by drawing epistemologically on the potentialities of the biography of scientific objects. This research note reveals a scientific discourse translated into materialities circulated in public spaces in the globalized Europe of the 1930s, with references from scientific power, in the context of Portugal's Estado Novo regime, enshrined in its 1933 constitution.


O 12º Congresso Internacional de Zoologia realizou-se em Lisboa, em 1935. Da sua memória concreta constam insígnias ­ estrela-do-mar ­ e caricaturas de zoólogos. A partir de investigação no Arquivo do Museu Nacional de História Natural e da Ciência/Universidade de Lisboa, pretendemos interrogar a cenografia material, pensada pelo zoólogo Artur Ricardo Jorge pela aproximação epistémica às potencialidades da biografia de objetos científicos. Esta nota de pesquisa pretende deixar a marca de um discurso científico traduzido em materialidades de circulação em espaço público, na Europa globalizante dos anos 1930, com referências de poder científico, no contexto do Estado Novo português, inaugurado, constitucionalmente, em 1933.


Assuntos
História Natural , Zoologia , Arquivos , Europa (Continente) , História do Século XX , Museus
4.
Hist. ciênc. saúde-Manguinhos ; 29(3): 853-861, jul.-set. 2022. graf
Artigo em Português | LILACS | ID: biblio-1405021

RESUMO

Resumo O 12º Congresso Internacional de Zoologia realizou-se em Lisboa, em 1935. Da sua memória concreta constam insígnias - estrela-do-mar - e caricaturas de zoólogos. A partir de investigação no Arquivo do Museu Nacional de História Natural e da Ciência/Universidade de Lisboa, pretendemos interrogar a cenografia material, pensada pelo zoólogo Artur Ricardo Jorge pela aproximação epistémica às potencialidades da biografia de objetos científicos. Esta nota de pesquisa pretende deixar a marca de um discurso científico traduzido em materialidades de circulação em espaço público, na Europa globalizante dos anos 1930, com referências de poder científico, no contexto do Estado Novo português, inaugurado, constitucionalmente, em 1933.


Abstract The material memory of the 12th International Congress of Zoology, held in Lisbon in 1935 includes insignias - the starfish - and caricatures of zoologists. Through an investigation of the archives at the University of Lisbon's National Museum of Natural History and Science, we intend to investigate the material landscape as conceived by the zoologist Artur Ricardo Jorge by drawing epistemologically on the potentialities of the biography of scientific objects. This research note reveals a scientific discourse translated into materialities circulated in public spaces in the globalized Europe of the 1930s, with references from scientific power, in the context of Portugal's Estado Novo regime, enshrined in its 1933 constitution.


Assuntos
Zoologia , Congressos como Assunto , Internacionalidade , Portugal , História do Século XX
5.
Talanta ; 221: 121546, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33076105

RESUMO

Capillary electromigration is a well-established commercial group of analytical techniques, and, alike other column separation systems, it often benefits from a preceding sample preparation step. This step not only improves the analytical performance of many methods and prolongs the equipment's life span, but it also makes some determinations possible. A remarkable sample preparation technique is molecular imprinting technology: by creating tailored polymers able to 'select' the targeted analytes, matrix effects are severely diminished. This review aims to provide an overview of all the published works that combine capillary electrophoresis and molecularly imprinted polymers (MIP). Although a literature search produced around 130 published analytical methodologies and 5 patents, authors believe that there is still plenty of room for interesting developments. Works ranged from the analysis of pesticides to pharmaceuticals or hormones, being the most common instrumental detection spectrophotometric. The combination between MIP and electrophoresis can be divided into two main categories depending on where the MIPs are placed within the analytical 'pipeline': off-column and in-column. Off-column consisted of MIP batch application previous to capillary injection. In-column approaches are more complex, and can be divided into coating, monolith, packed (these three being considered capillary electrochromatography), and dispersed particles (affinity capillary electrophoresis).


Assuntos
Eletrocromatografia Capilar , Impressão Molecular , Polímeros Molecularmente Impressos , Polímeros
6.
Electrophoresis ; 41(18-19): 1576-1583, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32683725

RESUMO

Aminoglycosides are a relevant class of antibiotics widely used by medics and veterinaries. There are a variety of reasons that make their determination relevant, such as quality control, environment and food contamination assessment, drug-release studies, among others. The lack of a chromophore makes aminoglycoside spectrophotometric detection particularly challenging, often requiring derivatization. In this work, an indirect detection method, making use of imidazole as a probe, applying CZE was successfully tested. It did not require derivatization, which simplified the sample preparation. Suitable figures of merit were obtained; recoveries between 95 and 105%, adequate repeatability and precision, correlation coefficients (r) above 0.998, and limits of detection (LODs) of 3.2 and 11 mg/L for gentamicin and paromomycin, respectively. As a proof-of-concept, it was also applied in a simple controlled release experiment that was well fitted using the Hill equation.


Assuntos
Aminoglicosídeos/análise , Antibacterianos/química , Eletroforese Capilar/métodos , Espectrofotometria Ultravioleta/métodos , Formas de Dosagem , Imidazóis/química , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
7.
Electrophoresis ; 40(22): 2929-2935, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31471917

RESUMO

Aldehydes are important compounds in a large number of samples, especially food and beverages. In this work, for the first time, cyclohexane-1,3-dione (CHD) was used as a derivatizing reagent aiming aldehyde (formaldehyde, acetaldehyde, propionaldehyde, and valeraldehyde) analysis by MEKC-DAD. The optimized separation of the derivates was performed using a voltage program (+20 kV, 0-15 min.; +23 kV, 15-17 min.) at a temperature of 26°C, and using as the running buffer a mixture containing 100 mmol/L of sodium dodecyl sulfate and 29 mmol/L of sodium tetraborate at pH 9.2, with maximum absorbance at 260 nm. CHD was compared with two other derivatizing agents: 3-methyl-2-benzothiazolinone hydrazone and phenylhydrazine-4-sulfonic acid. The CHD-aldehyde derivatives were also characterized by LC-MS. The calibration curves for all aldehydes had r2 above 0.999 and LODs ranged from 0.01 to 0.7 mg/L. The optimized methodology was applied in sugar cane brandy (cachaça) samples successfully. CHD showed to be an alternative derivatization reagent due to its stability, aqueous solubility, high selectivity and sensitivity, reduced impurities, and simple preparation steps.


Assuntos
Aldeídos/análise , Cromatografia Capilar Eletrocinética Micelar/métodos , Cicloexanonas/química , Análise de Alimentos/métodos , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
8.
MethodsX ; 5: 656-668, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30003050

RESUMO

This methodology is proposed to measure the fluxes of trace gases among microcosms and the atmosphere. As microcosm respiration we include both aerobic and anaerobic respiration, which may results in CO2, CH4, NO, N2O, N2, H2S and H2 fluxes. Its applicability includes the assessment of products biodegradability and toxicity, the effect of treatments and products on greenhouse gases fluxes, and the mineralization of organic fertilizers. A step by step procedure; the complementary parameters and good practices that might be taken into account to perform a microcosm experiment; and the tools nowadays available that could be useful in this respirometric methodology are presented. We included a spreadsheet with calculus examples. Samples were taken at 1; 30; 60 and 90 min after closing the microcosms to determine the gases fluxes. The dilution effect was negligible, as we present. Besides CO2, we have successfully quantified the fluxes of CH4 and N2O from the microcosms in a broad range of concentrations. This method is useful in technical and scientific studies, for instances to test new products and improve the understanding of microbial processes, respectively. •Simple materials are required to set up the microcosm.•Examples of (pre) treatments are given regarding water availability, fertilizer doses, pH adjustment and nutrients amendments.•The method was suitable to directly measure multiple trace gases fluxes, either produced or consumed during microcosm respiration.

9.
Talanta ; 187: 113-119, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29853022

RESUMO

Aldehydes are relevant analytes in a wide range of samples, in particular, food and beverages but also body fluids. Hydrazines can undergo nucleophilic addition with aldehydes or ketones giving origin to hydrazones (a group of stable imines) that can be suitably used in the identification of aldehydes. Herein, 4-hydrazinobenzoic acid (HBA) was, for the first time, used as the derivatizing agent in analytical methodologies using liquid chromatography aiming the determination of low-molecular aldehydes. The derivatization reaction was simultaneously performed along with the extraction process, using gas-diffusion microextraction (GDME), which resulted in a clean extract containing the HBA-aldehyde derivates. The corresponding formed imines were determined by both high-performance liquid chromatography (LC) with UV spectrophotometric detection (HPLC-UV) and capillary electrophoresis with diode array detection (CE-DAD). HBA showed to be a rather advantageous derivatization reagent due to its stability, relatively high solubility in water and other solvents, high selectivity and sensibility, reduced impurities, simple preparation steps and applicability to different separation and/or different detection techniques. Limits of detections (LODs) of the optimized methodologies (in terms of time and pH among other experimental variables) were all below 0.5 mg L-1, using both instrumental techniques. Furthermore, for the first time, the HBA-aldehyde derivatives were analyzed by LC with mass spectrometry (LC-MS), demonstrating the possibility of identification by MS of each compound. The developed methodologies were also successfully applied in the analysis of formaldehyde and acetaldehyde in several alcoholic beverages. This was also the first time GDME was combined with CE, showing that it can be a valuable sample preparation tool for electrophoresis, in particular by eliminating the interference of ions and inorganic constituents present in the samples.

10.
Electrophoresis ; 38(7): 1068-1074, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27990662

RESUMO

In this work, the use of a novel derivatization agent for the determination of aldehydes (in this particular case: formaldehyde, acetaldehyde, propionaldehyde, and valeraldehyde) using micellar electrokinetic chromatography is reported. The derivatization reaction is based on the reaction of aldehydes with benzhydrazide to form the corresponding derivates with maximum absorbance at 250 nm. The experimental conditions of the derivatization reaction as well of the separation were optimized. The adducts were separated with a +22 kV voltage at a temperature of 29°C. The adducts' separation was performed in less than 14 min using as the running buffer a mixture containing 110 mmol/L of sodium dodecyl sulfate and 27 mmol/L of sodium tetraborate at pH 9.45. Samples were injected using hydrodynamic mode (50 mbar × 5 s). The calibration curves were linear up to 15.0 mg/L with r2 above 0.99. Intra and inter-day precisions were in average 3 and 4%, respectively, and recoveries were in average of 95%. Limits of detection and quantification were around 0.5 and 1.5 mg/L, respectively. The developed method was successfully applied in the analysis of low molar weight aldehydes in yogurt and vinegar samples.


Assuntos
Aldeídos/análise , Aldeídos/química , Cromatografia Capilar Eletrocinética Micelar/métodos , Análise de Alimentos/métodos , Ácido Acético/análise , Hidrazinas/química , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes , Iogurte/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA